I am leaning towards night terrors, but would need more information. They are more common in boys and with night terrors, you can't console them. You just have to ride it out. Does he seem to know you are there or not? Does he eventually just seem to wake up and then be calm? They are different than nightmares because with nightmares you can wake them and comfort them and it's over. With night terrors, they have no memory of it the following morning.
You may want to make sure his bedtime is early enough and he's not overtired. Adequate sleep is a must. My whole website is dedicated to child sleep, so if you want to "pick my brain", just come on by!

Hi Diane! Thank you so much for checking out my site! It's good to hear you are napping your toddler well. ;-) Thank you for your congrats on my second son. He is a much better sleeper, so far, than my first so yes, I am getting some sleep, thankfully! Phew! LOL

Hi Pick Nick's Brain. Welcome to Work it, Mom! It's great to meet you. Congrats on the arrival of your second child! I enjoyed checking out your website--I so agree that sleep begets sleep. I make such an effort now to make sure my 17 month old toddler gets a good nap each day, as that makes all the difference to how well she sleeps at night. It's so critical! Speaking of sleep, I hope YOU can get some lately, what with two little ones to care for! Hope you had a nice weekend. :)